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The activity of a commercial alumina, after a preliminary characterization, was investigated in epoxidation\ud with soybean oil with aqueous hydrogen peroxide. Results show that the g-alumina was an efficient catalyst.\ud The role of the solvent in the epoxidation reaction in the presence of alumina was investigated. A “noinnocent”\ud solvent role was demonstrated. Moreover, the optimization of the methyl oleate epoxidation\ud reaction with alumina was eventually valuated, varying the type of the solvent and concentration of\ud hydrogen peroxide in order to obtain a product with commercial features

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In this paper, nine different catalysts have been used for the epoxidation of methyl oleate with hydrogen peroxide as oxidant. The prepared catalysts were mostly based on supported systems niobia–alumina and niobia–silica.\ud Experimental runs were carried out in a lab-scale reactor, keeping constant operating parameters such as reaction temperature (80 °C) and time (5 h), and molar ratio between oxidant and methyl oleate (equal to 4). Runs aimed at the quantitative evaluation of system conversion, yield and selectivity. Nb2O5/ SiO2 were found to be active in epoxidation reaction, in particular the catalyst with intermediate\ud niobia loading (6% w/w) showed very high conversion (77%) even if with a very low selectivity to epoxides (30%).\ud Instead, regarding the system based on Nb2O5/ Al2O3, both better activity and selectivity were reached. In particular, the material containing 12% of Niobia yielded the highest values for conversion (83%) and selectivity (89%). The results have been critically discussed through the outcomes of a deep characterization of the catalytic materials, carried out through porosimetric, X-ray diffraction, ultra violet and visible diffuse reflection, and Raman microscopy analyses.\ud The discussion highlighted the more relevant parameters able to influence the activity of niobia-based catalysts in the methylesters epoxidation

This work deals with the preparation of biolubricant basestocks through the ring-opening reaction of epoxidized soybean oil (ESO) by alcohols in presence of solid acid catalysts (SAC-13 resin). To this end, different experimental runs were carried out in a lab-scale reactor, analyzing the effect of the alcohol (methanol, ethanol, 2-propanol, 2-butanol), catalyst mass loading (from 1 to 10 wt % with respect to the oil mass) and operating temperature (60-90 • C). The main focus of investigation was oxirane conversion. The study was complemented by FT-IR, 1 H NMR and kinematic viscosity characterization of the different products of the ring-opening reaction. Experimental conversion data were fitted through a suitable kinetic model. Values of the best-fitting parameters in terms of rate constant, activation energy and catalyst reaction order were obtained, and were potentially useful for the design of an industrial process.

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